Browsing by Author "Pizarro, Gonzalo"
Now showing 1 - 6 of 6
Results Per Page
Sort Options
- ItemCase Report: Molecular Features and Treatment Options for Small Bowel Adenocarcinoma(2021) Cordova-Delgado, Miguel; Pizarro, Gonzalo; Pinto, Mauricio P.; Herrera, Maria Elisa; Garrido, MarceloSmall bowel adenocarcinoma (SBA) is a rare malignancy characterized by poor prognosis. Recent efforts have sought to elucidate the genetic landscape and the molecular drivers behind this disease. Herein, we report the main molecular alterations in two metastatic (stage IV) SBA patients. Interestingly, one of them had gene alterations that affected signaling pathways previously described for SBA. However, a second patient displayed previously unreported alterations in this particular tumor type. Based on these findings we discuss potential treatment options for patients affected by this rare, aggressive disease.
- ItemComplete response to immunotherapy plus chemotherapy after an unusual clinical response to afatinib and stereotactic radiosurgery in a patient with metastatic EGFR-mutant non–small-cell lung cancer(2020) Pizarro, Gonzalo; Pinto, Mauricio P.; Muñoz-Medel, Matías; Cordova-Delgado, Miguel; Bravo, M. Loreto; Nervi, Bruno; Sánchez, César; Ibañez, Carolina; Peña, José; Walbaum, Benjamín; Madrid, Jorge; Briones, Juan; Koch, Erica; Valbuena, Jose; Gonzalez, Sergio; Gejman, Roger; Acevedo, Francisco; Mondaca, Sebastian; Garrido, Marcelo; Vines, Eugenio; Galindo, Hector
- ItemContrast-enhanced mammography predicts pathological response after neoadjuvant chemotherapy in locally advanced breast cancer(2022) Canteros, Daniel; Walbaum, Benjamin; Córdova-Delgado, Miguel; Torrealba, Andrés; Reyes, Constanza; Navarro, María Elena; Razmilic, Dravna; Camus, Mauricio; Dominguez, Francisco; Navarrete, Orieta; Pinto, Mauricio P.; Pizarro, Gonzalo; Acevedo, Francisco; Sánchez, CésarIntroduction: Recently, contrast-enhanced mammography (CEM) has emerged as a reliable alternative to breast magnetic resonance imaging (MRI) for the assessment of pathological response in breast cancer patients. Our study sought to determine the diagnostic accuracy of CEM to predict pathological complete response (pCR) in patients who received neoadjuvant chemotherapy (NACT). Methods: We retrieved the medical records of patients who underwent NACT at our institution. Using post-surgery pCR, morphological evidence and CEM enhancement tumours were classified as follows: 1) radiologic complete response (rCR); 2) functional radiological complete response (frCR); and 3) non-complete response. Initially, we used multivariate analyses adjusted by clinical variables and frCR or rCR to determine which variables affected pathological response. Then, CEM diagnostic accuracy to discriminate pCR was assessed using receiver operating characteristic curves in univariate and multivariate models including either frCR or rCR. Results: A total of 48 patients were included in our study. Most patients (68.7%) were hormone receptor (HR)+ and 41.6% (20) of the patients achieved pCR. Using univariate logistic regression analyses we found that HR status, HER2 status, rCR and frCR had a significant impact on CEM diagnostic accuracy. Exploratory analyses found that CEM sensitivity was higher for HR− tumours. Multivariate logistic regression analyses found 60% sensitivity, 92.9% specificity and 79.2% accuracy in a model that included clinical variables and rCR. Conclusion: CEM is a reliable alternative to high-cost, time-consuming breast MRI that predicts pCR in patients undergoing NACT; CEM diagnostic accuracy was higher among patients who harboured HR− tumours.
- ItemPerchlorate and chlorate assessment in drinking water in northern Chilean cities(2023) Muñoz Arango, Diana Carolina; Torres Rojas, Felipe Ernesto; Tapia Flores, Natalia F.; Vega Muñoz, Marcela Natalia; Alvear, Cristóbal; Pizarro, Gonzalo; Pastén González, Pablo Arturo; Cortés Arancibia, Sandra; Vega Contreras, Alejandra Soledad; Calderón, Raúl; Nerenberg, Robert; Vargas, Ignacio; CEDEUS (Chile)Perchlorate and chlorate are endocrine disruptors considered emerging contaminants (ECs). Both oxyanions are commonly associated with anthropogenic contamination from fertilizers, pesticides, explosives, and disinfection byproducts. However, the soils of the Atacama Desert are the most extensive natural reservoirs of perchlorate in the world, compromising drinking water sources in northern Chile. Field campaigns were carried (2014–2018) to assess the presence of these ECs in the water supply networks of twelve Chilean cities. Additionally, the occurrence of perchlorate, chlorate and other anions typically observed in drinking water matrices of the Atacama Desert (i.e., nitrate, chloride, sulfate) was evaluated using a Spearman correlation analysis to determine predictors for perchlorate and chlorate. High concentrations of perchlorate (up to 114.48 μg L−1) and chlorate (up to 9650 μg L−1) were found in three northern cities. Spatial heterogeneities were observed in the physicochemical properties and anion concentrations of the water supply network. Spearman correlation analysis indicated that nitrate, chloride, and sulfate were not useful predictors for the presence of perchlorate and chlorate in drinking water in Chile. Hence, this study highlights the need to establish systematic monitoring, regulation, and treatment for these EC of drinking water sources in northern Chilean cities for public health protection.
- ItemProteogenomic analysis in an early onset diffuse gastric cancer patient revealed alterations in PIK3R1, TP53, SMAD4 and a potential role of the PI3K-AKT and EGFR pathways: a case report(2022) Cordova-Delgado, Miguel; Pinto, Mauricio P.; Pizarro, Gonzalo; Koch, Elard; Vargas, Cristian; Hernandez, Mauricio; Nourdin, Guillermo; Saldivia, Pablo; Paz Rodriguez, Maria Z.; Berkovits, Alejandro; Manque, Patricio; Rios, Juvenal A.; Garcia-Bloj, Benjamin; Garrido, MarceloBackground: Early-onset gastric cancers (EOGC) are poor prognosis hard-to treat malignancies that affect young individuals (<45 years old). Case Description: Herein we describe the case of a 26-year-old female EOGC patient that initially displayed stable disease after first-line CAPOX plus immunotherapy. However, patient eventually developed progressive disease and was consecutively switched to paclitaxel plus ramucirumab, and palliative irinotecan. In search for therapeutic alternatives a proteo-genomic analysis was performed in a tissue biopsy taken after the first progression. Our analyses found a total of 18 somatic mutations, including TP53 and PIK3R1, and a previously unreported germline alteration in the tumor suppressor SMAD4. Also, our proteomic analysis found 62 proteins previously documented as ???enriched in stomach cancer??? and AKT/mTOR and EGFR as pathways with therapeutic potential. Unfortunately, the clinical utility of AKT/mTOR inhibitors or EGFR targeted therapies could not be assessed. Conclusions: As explained above EOGC is a growing health concern that affects young individuals. Furthermore, the reported case displayed a poor response to standard therapy including checkpoint inhibitors and chemotherapy despite the presence of biomarkers that predict a favorable outcome. Future studies should adopt alternative approaches to find novel, more effective therapies.
- ItemQuantitative Ocular Surface Changes in Patients Undergoing Immune Checkpoint Inhibitor Therapy(2024) Chen, Kevin; Bruron, Maria Carolina Ibanez; Mondaca, Sebastian; Pizarro, Gonzalo; Liberman, Paulina; Berkenstock, Meghan K.PurposeTo describe the clinical course and evaluate treatment of ocular surface changes in patients receiving immune checkpoint inhibitor (ICI) therapy.MethodsMultiple markers of ocular surface dryness were evaluated in 16 patients on ICI therapy. The Wilcoxon rank-sum test was used to determine the significant change in the initial and final ocular surface indices.ResultsFifty percent of the eyes demonstrated worsening Schirmer I scores; 29% showed an increase in lissamine green staining. During follow-up, 43% of patients experienced a decline in OSDI scores. Treatments included preservative-free artificial tears (88%), cyclosporine (25%), topical corticosteroids (31%), warm compresses (25%); punctal plugs (13%). Median follow-up time was 3.4 months (range:0-79 ); median ICI treatment duration was 7 months (range:1-40). Four patients died during the observation period.ConclusionA significant proportion of patients experience changes in ocular surface markers while treated with ICIs. Medical intervention can lead to stabilization of ocular surface disease.